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Precise genome editing of plants has the potential to reshape global agriculture through the targeted engineering of endogenous pathways or the introduction of new traits. To develop a CRISPR nuclease-based platform that would enable higher efficiencies of precise gene insertion or replacement, we screened the Cpf1 nucleases from Francisella novicida and Lachnospiraceae bacterium ND2006 for their capability to induce targeted gene insertion via homology directed repair. Both nucleases, in the presence of a guide RNA and repairing DNA template flanked by homology DNA fragments to the target site, were demonstrated to generate precise gene insertions as well as indel mutations at the target site in the rice genome. The frequency of targeted insertion for these Cpf1 nucleases, up to 8%, is higher than most other genome editing nucleases, indicative of its effective enzymatic chemistry. Further refinements and broad adoption of the Cpf1 genome editing technology have the potential to make a dramatic impact on plant biotechnology.

The effect of basicity and Cr2O3 content on vitrification of the CaO-MgO-SiO2-Al2O3-Fe2O3-Cr2O3 system during a melt-quenched process and the crystallization and mineralogical evolution of the obtained glasses were investigated. X-ray diffraction (XRD) analysis of the quenched samples indicated that lower basicity (B = 0.8 and 1.0) and lower Cr2O3 concentration (< 4 wt pct) were favorable for glass formation. B = 1.25 and 1.5 samples were crystallized much easier, with most of the Cr captured in the spinel structure. Differential scanning calorimetry measurements revealed that the glass transition and crystallization temperatures both increased upon increasing the heating rate from 5 K to 20 K (°C)/min. In addition, compared with the samples without Cr2O3, the crystallization activation energy of those with Cr2O3 were lower for the same basicity. For glassy samples heated above 1228 K (955 °C), XRD and scanning electron microscopy characterizations suggested that diopside and wollastonite were the main precipitated phases for the samples with B = 0.8, whereas akermanite and wollastonite were the main phases for samples with B = 1.0.

The braking mode of the battery electric urban bus (BEUB) is different from the friction braking of the traditional fuel bus due to the introduction of a regenerative braking system. The intervention of electromagnetic braking changes the working condition of the main reducer gears, thus affecting their service lives. Based on the Urban Dynamometer Driving Schedule (UDDS) driving cycle condition, the stress–time history of the main reducer gears is calculated. Combined with the static analysis results and the S-N curve of the material, the fatigue lives of the main reducer gears considering electromagnetic braking and traditional friction braking are analyzed. The reverse torque on the driving axle during electromagnetic braking is taken into account to be closer to the real situation. Results show that, under the electromagnetic braking mode, the bending fatigue lives of the tooth root on the convex and concave surfaces of the pinion are 78.5% and 78.9% of that under the traditional friction braking mode, respectively, while the contact fatigue life of the pinion working surface is 78.2% of that under the friction braking mode, indicating that the introduction of the regenerative braking system into the BEUB will cause a significant reduction in the service life of the main reducer gears. This study provides a high-precision fatigue life calculation method for the BEUB main reducer gears and the accurate prediction of their remaining life.

Sugar beet ( Beta vulgaris L.) is an important sugar-producing and energy crop worldwide. The sugar beet pure line IMA1 independently bred by Chinese scientists is a standard diploid parent material that is widely used in hybrid-breeding programs. In this study, a high-quality, chromosome-level genome assembly for IMA1was conducted, and 99.1% of genome sequences were assigned to nine chromosomes. A total of 35,003 protein-coding genes were annotated, with 91.56% functionally annotated by public databases. Compared with previously released sugar beet assemblies, the new genome was larger with at least 1.6 times larger N50 size, thereby substantially improving the completeness and continuity of the sugar beet genome. A Genome-Wide Association Studies analysis identified 10 disease-resistance genes associated with three important beet diseases and five genes associated with sugar yield per hectare, which could be key targets to improve sugar productivity. Nine highly expressed genes associated with pollen fertility of sugar beet were also identified. The results of this study provide valuable information to identify and dissect functional genes affecting sugar beet agronomic traits, which can increase sugar beet production and help screen for excellent sugar beet breeding materials. In addition, information is provided that can precisely incorporate biotechnology tools into breeding efforts.

Basic oxygen furnace (BOF) slag was modified by adding 3.5% SiO2 and holding at 1673 K for 0, 5, 40, 90, 240, or 360 min. Kilo-scale modification was also carried out. The growth, stratification, and liberation of P-rich C2S in the modified slag were investigated. The optimum holding time was 240 min, and 90% of C2S grains were above 30 μm in size. The phosphorus content increased with holding time, and after modification, the phosphorus content in C2S was nearly three times higher than that in the original slag (2.23%). Obvious stratification of C2S was observed in the kilo-scale modification. Upper C2S particles with a relatively larger size of 20–110 μm was independent of RO (FeO-MgO-MnO solid solution) and spinel, which is favorable for liberation. Lower C2S was less than 3 μm and was embedded in spinel, which is not conducive to liberation. The content of phosphorus in upper C2S (6.60%) was about twice that of the lower (3.80%). After grinding, most of the upper C2S existed as free particles and as locked particles in the lower. The liberation degree of C2S in the upper increased with grinding time, from 86.02% to 95.92% in the range of 30–300 s, and the optimum grinding time was 180 s. For the lower slag grinding for 300 s, the liberation degree of C2S was 40.07%.

La 0.8 Sr 0.2 MnO 3 samples with rhombohedral, orthohombic and monoclinic structures were prepared by solid state reaction, sol-gel and co-precipitation methods, respectively. Lattice parameters, grain size, morphology, infrared absorption and emissivity of samples were investigated. The results indicated that the average crystallite size calculated from XRD result and particle size of orthohombic sample were smaller than those of the other two samples, and honeycomb shape grains were observed in orthohombic sample. Due to lower crystal symmetry, Mn-O stretching vibration peaks of the three samples shifted to higher infrared wavenumber. According to the theory of wave optics and Kirchhoff law, bigger rhombohedral sample showed higher emissivity than monoclinic one. However, due to the honeycomb structure of orthohombic sample, repeated reflection and scattering led to the increase of absorption, and orthohombic sample exhibited the highest emissivity.

A novel visible-light-response photocatalyst was prepared through the heat treatment of Ti-bearing blast-furnace slag with sodium nitrate and subsequently leaching processes in which most of the SiO2, Al^sub 2^O3, and MgO in Ti-slag (TS) have been separated. The photocatalytic activity of the TTS was studied by observing the evolution of H2 under the UV-Vis and visible light. Compared with the TS and commercial perovskite CaTiO3, the sample prepared exhibited an exclusive visible-light-response activity and enhanced H2 evolution.[PUBLICATION ABSTRACT]

We report an Agrobacterium-mediated transformation system that can generate marker-free transgenic sorghum [Sorghum bicolor (L.) Moench] from a public line [P898012] using standard binary vectors with bar as a selectable marker. Eight co-cultivation conditions were examined for their effect on transformation. The average transformation frequencies were 0.4 and 0.7% for pZY101-TC2 and pZY101-SKRS, respectively, derived from binary vector pZY102 and containing bar and target gene(s) in separate T-DNA regions. A low selection pressure (2.5 mg l⁻¹ DL-phosphinothrithin, PPT) was deployed during callus induction in combination with rapid selection to generate plants from 80 independent events, all but three of which were fertile and set seed. PCR and Southern analyses showed that 36 out of 80 events contained both bar and the target gene(s) (an average co-transformation frequency of 45%). Seedlings of the T1 generation transmitted T-DNAs with target gene(s) and bar gene independently, generating a fraction of progeny with only the target gene(s).

The distribution behavior of vanadium in factory steel slags with high basicity (CaO/SiO 2 ) and enrichment of vanadium in slag modified by SiO 2 and Al 2 O 3 were investigated. The mineralogical phases and vanadium distribution were characterized by scanning electron microscopy (SEM), energy disperse x-ray spectrometry (EDS), and powder x-ray diffraction (XRD). The results indicate that vanadium is distributed in the major phase of calcium silicate and the phase of the matrix in steel slag with high basicity. The V 2 O 5 contents in the dicalcium silicate phase increase with declining basicity of steel slag, whereas, in the slag modified by SiO 2 and Al 2 O 3 , V is concentrated in the solid solution of Ca 3 [(V, P, Si)O 4 ] 2 (the V-enrichment phase), which is identified with the results based on synthetic steel slag containing vanadium. The relation between chemical composition and crystallization behavior and grain size of Ca 3 [(V, P, Si)O 4 ] 2 is also discussed. It is found that high MgO in the slag will form magnesium aluminate, and the V-enrichment phase grains grow larger than that obtained in synthetic slag.

Bicationic M x Ca 2−2 x SiO 4 : x Eu 2+ [M = Mg, Sr, ( x  = 0.005–0.16)] phosphors were prepared by high temperature solid-state method. The evolution of luminescence structure, space occupying mechanism and energy transfer were studied by XRD and PL spectra. Mg 2+ /Sr 2+ cationic sites induced the matrix phases as β-Ca 2 SiO 4 (Mg, Sr = 0.005–0.04), β-Ca 2 SiO 4 mixed with Ca 14 Mg 2 (SiO 4 ) 8 (Mg = 0.08–0.16), or α H ʹ-Ca 2 SiO 4 (Sr = 0.08–0.16), Mg occupied Ca 2 position in β-Ca 2 SiO 4 to form structural unit 1, and Sr occupied Ca 1 position in β-Ca 2 SiO 4 to form structural unit 2. β-Ca 2 SiO 4 is the preferred host site for Eu 2+ within the matrix, and Eu 2+ ions preferentially occupy the Sr/Ca 2 site. For M x Ca 2−2 x SiO 4 : x Eu 2+ [M = Mg, Sr, ( x  = 0.005–0.16)] phosphors, due to the 4f 6 5d 1  → 4f 7 jump of Eu 2+ ions, it exhibits 450–650 nm broadband yellow-green emission under 345 nm excitation, and the redshift of the emission spectra is attributed to the contraction of CaO 7 polyhedra by the movement of the SiO 4 tetrahedra leading to a weakened crystal field of the Eu 2+ ion crystal field weakening. Sr 2+ cationic sites provide an improvement in the luminescence thermal stability of M x Ca 2−2 x SiO 4 : x Eu 2+ [M = Mg, Sr ( x  = 0.005–0.04)], as is demonstrated by its energy level potential barrier Δ E  > 0.34 eV at 150 °C. The Mg 2+ /Sr 2+ cationic sites are provided to enable phosphors to achieve green to yellow light, promising applications for multicolor tunable WLED lighting.